Cellulose oxide, gelatin and microfibrillar collagen are known to be conventional styptic materials used to treat wounds, and are already used in pharmaceutical products and medical equipment. In addition, the following Patent Documents 1 and 2 disclose carboxymethyl cellulose having an action that promotes cellular adhesion. On the other hand, although styptic materials of the prior art protect the surface of a wound by absorbing moisture and swelling to form an adhesive film, excessive absorption of moisture causes the structure thereof to dissolve resulting in the problem of difficulty in retaining shape, and thereby making it difficult to be used at an affected area where there is heavy bleeding such as in the case of using for hemostasis at a puncture site following dialysis,
In addition, in the case of a wound, present on human skin, for example, wound protective materials such as surgical dressing or wound covering materials are used so as to protect the wound site, and the following Patent Document 3 describes a soluble wound-healing styptic cellulose fiber in which the degree of substitution of the CMC is 0.5 to less than 1.0. In addition, the following Patent Document 4 describes that, in the case of applying CMC to a wound, there are no residual contaminants having the risk of causing inflammation and so forth at the wound site. However, since CMC having a degree of substitution of 0.5 or more gels excessively rapidly after absorbing liquid, it undergoes a change in form by contracting or dissolving, thereby resulting in problems in terms of use as a wound covering material.
In general, adhesive skin patches for medical use are required to have properties that enable them to conform to movement of the skin and surface irregularities in the skin. Consequently, gauze using cotton or silk was widely used as wound covering materials of the prior art due to its thinness and softness. However, since gauze lacks absorbency and liquid retention, if the amount of exudate from a wound is large, it is unable to suitably absorb the exudate resulting in the occurrence of leakage, and thereby causing soiling of clothing or bed sheets and the like and resulting in an unhygienic situation, while also resulting in the bother of having to frequently replace the gauze in order to prevent leakage of exudate. In addition, although some wound covering materials contain absorbent materials in the manner of foam materials, the presence of an absorbent material resulted in the problem of adhesion of the material to the wound surface, and since this also caused the wound to dry as a result thereof, there was the problem of healing being slower in comparison with healing in a moist state.